The present disclosure relates generally to an arrangement for, and a method of, retrieving items associated with radio frequency (RF) identification (RFID) tags sequentially arranged in a list.
Radio frequency (RF) identification (RFID) technology is becoming increasingly important for logistics concerns, material handling and inventory management in retail stores, warehouses, distribution centers, buildings, and like venues. An RFID reader, also known as an interrogator, may be held and operated by an operator walking about a venue to interrogate and read any RFID item tags in its coverage range. Each item tag is usually attached to, or associated with, an individual item, or to a package for the item, or to a pallet or container for supporting or containing multiple items. Each item tag typically includes a tag antenna for receiving and/or transmitting RF waves, and an integrated circuit chip that typically has a power management section, a radio section, and frequently a logic section containing a control microprocessor, a memory, or both. The RFID reader transmits an RF interrogating signal, and each item tag, which senses the interrogating signal with its tag antenna, responds by transmitting an RF return signal from its tag antenna. The item tag either generates the return signal originally, or reflects back a portion of the interrogating signal in a process known as backscatter. The return signal or payload may be decoded into data, such as a tag identification (ID), by the reader and/or by a host server that is in communication with the reader. The decoded data identifies, counts, or otherwise interacts with the associated item.
In such venues, it is sometimes necessary to retrieve a plurality of RFID-tagged items from a list. For example, the list could be a shopping list, also known as a pick list, of RFID-tagged items ordered by a customer; or a list of perishable RFID-tagged items that are past their expiration dates; or a list of RFID-tagged items that have not been read for a long time, but also have not been seen departing the venue; or a list of RFID-tagged items thought to be stolen; or a list of RFID-tagged items that have recently been moved onto a sales floor; or, in brief, any list or compilation of RFID-tagged items that are deemed to be of interest. To retrieve the RFID-tagged items from the list using the handheld RFID reader, the operator must walk through the venue until the first RFID-tagged item on the list is found and read, and then continue walking through the venue until the second RFID-tagged item on the list is found and read, and so on for each RFID-tagged item on the list in sequential numerical order.
However, this retrieval method has proven to be a very time-consuming, laborious, and inefficient process. The operator must first walk through the venue during a first pass to hunt for, and find, the first RFID-tagged item on the list, and then either backtrack or continue walking through the venue during a second pass to hunt for, and find, the second RFID-tagged item on the list, and then repeat these actions during multiple passes to hunt for, and find, the remaining RFID-tagged items on the list in sequential order. During each pass, the operator is effectively blind, because he/she does not know if he/she is currently near the next RFID-tagged item on the list, or whether the operator has walked past and bypassed other RFID-tagged items that are located further down the list, thereby requiring the operator to return one or more times to retrieve the bypassed RFID-tagged items. The larger the venue, the higher the inefficiency, and the more laborious and time-consuming is the retrieval process.
Accordingly, it would be desirable to reduce the time and labor involved in retrieving all the RFID-tagged items from a list, and to increase the efficiency of the retrieval method, by non-sequentially reading the tags from the list in a non-ordered sequence.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and locations of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The arrangement and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.